Add fuzzer infra to blink and fuzz CSS parser

third_party/WebKit/Source/platform/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//testing/test.gni")
 import("//third_party/WebKit/Source/build/scripts/scripts.gni")
 import("//third_party/WebKit/Source/config.gni")
@@ skipping 650 matching lines @@
 
 if (current_cpu == "x86" || current_cpu == "x64") {
   source_set("blink_x86_sse") {
     sources = blink_platform_sse_files
     deps = [
       ":blink_common",
     ]
   }
 }
 
+# This source set is used for fuzzers that need an environment similar to unit
+# tests.
+source_set("blink_fuzzer_test_support") {
+  testonly = true
+  visibility = []  # Allow re-assignment of list.
+  visibility = [ "*" ]
+  sources = [
+    "testing/BlinkFuzzerTestSupport.cpp",
+    "testing/BlinkFuzzerTestSupport.h",
+  ]
+  deps = [
+    ":platform",
+    ":test_support",
+    "//content/test:test_support",
+    "//mojo/edk/system:system",
+  ]
+}
+
 # Fuzzer for blink::MHTMLParser.
 fuzzer_test("mhtml_parser_fuzzer") {
   sources = [
     "mhtml/MHTMLFuzzer.cpp",
   ]
   deps = [
     ":blink_common",
     ":platform",
     ":test_support",
   ]
   dict = "//testing/libfuzzer/fuzzers/dicts/mhtml.dict"
   seed_corpus = "//third_party/WebKit/LayoutTests/mhtml"
   additional_configs = [
     "//third_party/WebKit/Source/wtf:wtf_config",
     "//third_party/WebKit/Source:config",
   ]
 }